Former Green Goblin Willem Dafoe will join the DCEU this fall when Justice Leaguehits theaters. His Aquaman character will debut in the DC superhero extravaganza before filling a much larger role in James Wan’s Aquaman. And while things have been relatively quiet around Dafoe’s Nuidis Vulko and the role he’ll play in the films, the actor has confirmed that he won’t look or be exactly like his comic book counterpart.

While discussing his role as death god Ryuk in Death Note at the junket for the Netflix movie on Friday, Dafoe spilled a few extra details about his Vulko, a scientific advisor to Atlantis in the comics. The actor said he’ll only make a cameo in Justice League, but that he’ll play a more essential role inthe Wan film. “Aquaman is the important thing,” he said. Dafoe went on to tell me that his version of the Atlantean won’t completely resemble the character in the DC Comics:

There’s been some adjustments. Not even adjustments – it’s like anything, you use the source material and something is born from that. But I don’t really look like he does in the comic, and his role is slightly different. He is an advisor, but he’s also sort of a mentor to Aquaman.

A little background: In the comics, Vulko is an advisor to the Atlantean superhero. But throughout the comics Vulko also has an on-and-off again alliance with Aquaman, and at one point he even opposes the superhero’s rule. There’s a chance Wan’s version of the character might reflect this. When I asked Dafoe whether Vulko is a good guy in Aquaman, he said yes, but hinted that there’s some room for variation:

I’d say so. If you want to get down to those kind of categorizations. I don’t need to, I know why people do it because we’ve got to describe things sometimes. Everybody’s a mix, [laughs] good and bad.

As far as the character’s look, when Vulko was first introduced in 1967’s Brave and Bold #73 he was illustrated as buffed and balding with dark brown hair. But for Aquaman #35, artist Nick Cardy redesigned Vulko as much older with white hair, winged out on the sides and a fancy Colonel Sanders-style ‘stache. But based on a leak of Dafoe’s Funko Pop character toy from earlier this week, we have a better idea of how different his Vulko will be. The toy (via Screen Rant) shows Dafoe’s scientist sporting a full head of long brown hair, no facial hair, and armor. However Dafoe looks in Aquaman, that long flowing hair is certainly going to look cool underwater.

The Death Note actor told me that the majority of his scenes were shot underwater. He echoed some of Wan’s previous comments about the technical complications of shooting underwater, but gave a little more insight on how the shooting process works:

Most of my scenes are underwater. Some are not. So much of it, because we’re talking, and shooting underwater is a lot of ways impractical because you’re limited to what you can do with sets. It’s more about shooting them dry for wet, and then the effects do certain things to give the water feel. But we aren’t doing the scenes underwater, but we are in harnesses and on wires. There is movement. It’s not like were all sitting around pretending were underwater like this [stands up still], we’re swimming around, we’re moving. So that should be really beautiful.

We won’t get to see Dafoe underwater until Aquaman hits theaters on December 21, 2018, but we’ll get our first look at Vulko in Justice League on November 17. And before that, Dafoe lends his voice to the eerie death god of Death Note, hitting Netflix August 25.